Now that Robert Pattinson has reconciled with a contrite Kristen Stewart, a move that conveniently comes just in time for them to promote "Breaking Dawn -- Part 2" together, he's venturing out for some fun.

On Sunday night, he joined a posse of male pals for a private Black Keys concert at the Sayers Club in Los Angeles, where, by all accounts, he wasn't acting like someone who'd had his heart broken after a very public betrayal.

"He had a smile plastered across his face during the entire show," a source tells People mag. "He bobbed his head to almost every song. When he wasn't rocking out, he sipped on beer and spent time texting."

The actor, dressed down in a backwards baseball cap and a short-sleeved shirt, puffed on an electronic cigarette and graciously posed for photos with a handful of fans.

"Rob was definitely enjoying the music, getting more into it as the set went on," an eyewitness relays to Us Weekly, adding that he "seemed really happy and comfortable all night. … In between songs he would make comments or joke around with his friends."

The show ended around 10 p.m., but Rob stayed a while longer to have another drink with his buddies.

Meanwhile, with his "very deep connection" with Stewart mended, and the two supposedly once again shacking up, he's apparently growing comfortable venturing out with her again.

A spy reportedly saw Robsten hanging at a Hollywood bar on Monday night. And once again, K.Stew appeared to take a cue from Rob, because, like him, she was said to be sucking on an electronic cigarette.